A workpiece clamp is disclosed for pressing first and second workpieces into engagement by a chucking tool (6) and a counter-holding device (7) supported by a frame (5). A pair of clamping jaws (11,12) with spiral shaped clamping surfaces (13,14) are pivotally mounted on the clamping jaw support (8)...http://www.google.com/patents/US6189878?utm_source=gb-gplus-sharePatent US6189878 - Clamp for workpieces
